Abstract

In this paper computer simulation is presented for dicode pulse position modulation (DiPPM). DiPPM system offers good performance and operates at only twice the original PCM, thus it is very simple to implement in comparison to other PPM modulations. This makes DiPPM an extremely attractive modulation scheme for indoor optical wireless applications. MATLAB/Simulink has become the universal mathematical and modelling tool in most universities and research laboratories around the world. Studying complex models in optical link communications may be simplified by using simulation models so that real and industrial applications can be approached.The DiPPM is implemented over a diffuse optical wireless link using an LED at a wavelength of1550nm and data rate of 1Gb/s. The data sequence, coded by using DiPPM coder, is convolved withthe diffuse optical link then received and decoded by DiPPM coder to get the original data signal. The indoor diffuse channel model which considers additive white Gaussian noise (AWGN) model as more appropriate for significant background light has been simulated and bit error rate (BER) has been calculated.